Allied Irish Banksposted its first ever full-year net loss on Tuesday after being burned by exposure to Ireland's property market crash, saying the outlook and environment remained extremely challenging.

Allied Irish's net loss of 2.3 billion euros ($3.1 billion), its first time in the red since its foundation in 1966, compared with a loss of 2.9 billion euros expected by analysts based on Thomson Reuters I/B/E/S, and an 890 million euro profit in 2008.

Ireland's second biggest bank by market value said its 2009 operating profit before provisions increased slightly from the previous year to almost 3 billion euros, but it swung into the red after taking provisions mainly on loans to the construction and property sector.

Allied Irish, in which the government last year acquired a 25 percent indirect stake, will transfer property loans worth up to 23 billion euros to the National Asset Management Agency (NAMA), Ireland's bad bank, it said, slightly below an earlier estimate of 24 billion euros.

In 2010 AIB will prioritize restructuring and restoring its businesses to underpin viability, and renewing the group's credibility amongst all its stakeholders, it said in a statement.

(Reporting by Andras Gergely; Editing by Mike Nesbit)

($1=.7395 Euro)